This invention relates to a method of forming an efficient thin film tin-oxide electron emitter cold cathode.
It is known that tin oxide (SnO.sub.2) is a cold electron source that does not require an active metal coating to achieve appreciable emission. Heretofore, the tin oxide cold cathode has been formed by spraying tin oxide on a hot substrate. The difficulty with the tin oxide cold cathode fabricated by the aforedescribed method is that its emission is not stable. This obviates its use in devices which utilize cold cathodes such as solid state amplifiers.